So the NEB clutch assy needs a spacer to bring the sprocket in alignment while the AMC clutch doesn't. And because of the spacer, some of the shaft's thread is "lost".
- Knut
P11 basket case
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That old AMC clutch is starting to look better and better every day.
Mine needs a new center, although the old clutch does still work. Unfortunately, Andover ran out of old AMC clutch centers. Have to find another source.
Junglebiker
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Yes! a little heat was all that was needed. I don't know how hot I got it, not super hot, but definitely to hot to handle bare handed.
I originally thought the same as you--that I could remove both spacers and put the outer one back if I wanted to, but what looks like another spacer under the fully visible one is not a spacer at all--it is actually a short sleeve with a wall thickness of not more than .040" I think. Also the hole in that plate is not big enough to fit over the splines on the shaft.
On a related note--the spacer I made up to go behind the clutch is actually a little too thick--the drive chain at the engine end is about .040" closer to the inner primary case than it is at the clutch end. I need to examine this a little more closely to see if the sprockets are really out of line or if the difference is in the shape of the inner primary cover, not in sprocket alignment. If I am correct, I may need to reduce the thickness of the spacer behind my cutch from .175" to .135".
Curiously, it seems to me that the "original type" clutch I have on hand here would have been waaaaaay out of line. By about .165", maybe. Not certain about that.
Motorson and I looked into the Commando shaft idea some time ago, but there was some reason why it wouldn't work. The fact that a different clutch is offered for the Commando seems to support the fact that they are not interchangeable. Maybe when I am at the shop this afternoon I'll compare a Commando and an Atlas shaft and see if I can figure out what the reason is.
Junglebiker
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I am reasonably certain that the one I have can be used satisfactorily with the centre plate removed, but other options might exist. Either a more appropriately shaped centre could be obtained from one of the suppliers of NEB clutch parts, or that the one supplied could be modified on a lathe in such a way as to leave even more threads exposed upon assembly.
A "more appropriately shaped" centre hub would have a longer boss sticking out of the backside of the clutch assembly, (thereby negating the need for a spacer like the one I made), and less materiel on the front side (where the nut goes).
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Thanks for the update. Got ya on the rest of your experience with the clutch. I was living in a positive fantasy land when I thought that lower part might work behind the clutch. If I had been paying a little more attention it would have been obvious that the spines on the shaft would not go through it. Also have never seen a Commando mainshaft, so have not a clue if it would work either.
Junglebiker
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Okay, he we go. Here are two shafts side-by-side. The bottom one is like the one in my gearbox, the top one is what I believe to be a Commando one, but honestly I don't know a lot about Commandos, so I can't be 100% certain. The upper shaft does look like a more modern design to me, as it has provision for an o-ring seal on the clutch end to keep gearbox oil in the gearbox:
Close-ups:
Just looking at the two side-by-side, I suspect that even on the Commando shaft you woul dat least need to removed the sleeve behind the bolted-on plate so that the end of the splines could butt up against the backside of the bolted-on plate. Even so, I'm not sure that the clutch sprocket would line up properly with the drive sprocket. I'm sure it could all be made to work, but yeah, it would have to be "made to work".
I would like to make it clear at this point that I would welcome the input of anybody who has installed one of these clutches successfully in a P11 or Atlas before. By all means, if you see what I am doing wrong, please reply! I'm reasonably sure I have found a solution that will work just fine, but if you see what I did wrong, let me know.
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Yes, that is a Commando mainshaft.
It you were to try to use a stock Commando clutch, the first issue would be the primary chain - the Commando uses a triplex chain. I am sure if to you wanted to make it work (and somebody likely has) you could, but it would require some machine work.
The plus side is the Commando clutch can be made to work absolutely lovely with not a whole lot of work: light lever pull and positive engagement.
FWIW
Junglebiker
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Right. But what about a NEB clutch (ostensibly intended for an Atlas or P11) on a Commando shaft?
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The groove is for the Commando clutch location circlip, item 53, not an O-ring.
Andover Norton Parts Drawings - Genuine Andover Norton Factory Parts - Commando Parts
Andover Norton Parts are the only Norton spare parts in the market manufactured to original drawings, within the factory-approved tolerances, from the correct materials, and with the correct finish.
andover-norton.co.uk
Junglebiker
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STOP THE PRESSES!!!
Spacer behind the clutch basket doesn't work. Torquing down the nut on the clutch hub ends up locking up the transmission. I was doing some double checking and discovered that I could not get the gearbox to work properly. Long story short, I eventually determined that torquing down the hub centre nut with the spacer behind it causes the hub center to be tightened up against the countershaft. I know I'm not describing it very well, but suffice it to say that by virtue of the gearbox design, the clutch hub center must be tightened against the end of the splines on the mainshaft.
It all makes perfect sense, believe me....
The good news is that the spacer simply isn't needed. I took it out, reinstalled the center hub (without the bolt-on plate, but WITH the short sleeve) and all seems fine. In fact, now the primary drive sprockets line up properly, too.
Like Edison, I have to find 1000 ways that don't work before I find the one that does.
Spacer behind the clutch basket doesn't work. Torquing down the nut on the clutch hub ends up locking up the transmission. I was doing some double checking and discovered that I could not get the gearbox to work properly. Long story short, I eventually determined that torquing down the hub centre nut with the spacer behind it causes the hub center to be tightened up against the countershaft. I know I'm not describing it very well, but suffice it to say that by virtue of the gearbox design, the clutch hub center must be tightened against the end of the splines on the mainshaft.
It all makes perfect sense, believe me....
The good news is that the spacer simply isn't needed. I took it out, reinstalled the center hub (without the bolt-on plate, but WITH the short sleeve) and all seems fine. In fact, now the primary drive sprockets line up properly, too.
Like Edison, I have to find 1000 ways that don't work before I find the one that does.
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Junglebiker
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Thanks!The groove is for the Commando clutch location circlip, item 53, not an O-ring.
Andover Norton Parts Drawings - Genuine Andover Norton Factory Parts - Commando Parts
Andover Norton Parts are the only Norton spare parts in the market manufactured to original drawings, within the factory-approved tolerances, from the correct materials, and with the correct finish.andover-norton.co.uk
I am surprised learning about the short sleeve. I guess it's seen in entry #195 and it appears to ride on the threads. That's bad engineering! Is it really needed? Is it a spacer for the inner bearing race?
What keeps the NEB clutch assembly in position axially? The AMC clutch hub slides on the splines and is kept in place by the tapered end of splines. That's why the clutch nut doesn't need a high torque figure.
When you say all seems fine, you haven't solved the thread/nut issue, have you?
- Knut
Junglebiker
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Yes, I have. In the end, all I had to do was remove the bolted-on plate. Remove the three counter-sunk screws, the plate they retain and simply install. Do not put a spacer behind the clutch--at first I did not understand that the NEB clutch locates on the end of the countershaft splines. The NEB is made a little differently from what you describe, the clutch does not move on the splines once installed.
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Thanks for posting your experience installing the NEB clutch in a stock P11 primary case. Very helpful info for anyone coloring outside the lines with performance parts.
I'm going to have to do it. I've got other issues behind the primary with the spacing of the drive sprocket I installed on the gearbox. It has the wrong offset, and a 530 chain is grinding on things it should not grind on. So it all has to come off and might as well try the NEB clutch while I'm at it.
I'm going to have to do it. I've got other issues behind the primary with the spacing of the drive sprocket I installed on the gearbox. It has the wrong offset, and a 530 chain is grinding on things it should not grind on. So it all has to come off and might as well try the NEB clutch while I'm at it.
Junglebiker
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Moving on. I got some parts in from Baxter Cycles. Oil tank mounts, (I decided not to make these myself, simply in the interest of saving time, and because, let's face it, I'm unlikely to have hade a set that looked as nice as these):
These were really nicely made, but I made a huge mistake when I installed them--they are apparently made all out of stainless steel, including the studs and nuts and I failed to put any anti-seize on the threads before assembly. As a result, one nut seized while installing it and I was forced to cut it off and replace it with another. Then another seized while I was trying to disassemble it in order to put anti-seize on it (oh, the irony!), and I had to cut that nut off as well. In the end I had to run a die over the threads of both of the studs from which I had cut the nuts and then put non-stainless nuts on. It was a fiasco of my own making, but it ended up alright. Just beware! Use anti-seize when using stainless nuts on stainless bolts or studs!
head stay, also from Baxter. Aluminum this time.
Here's the Burkhardt magneto cap. It would not fit at first on my Hunt magneto, but there was plenty of material available to make it fit after some time with a sanding drum equipped Dremel. I went with the Burkhardt for a couple reasons, 1.) because I like the threaded connectors that hold the spark plug wires in and 2.) because I haven't seen anybody else do it! Preliminary testing shows a nice hot spark, as there should be.
I've got a question for you guys. What goes here, on this big threaded plug? It looks like a huge banjo fitting should go here, but I don't seem to have one:
These were really nicely made, but I made a huge mistake when I installed them--they are apparently made all out of stainless steel, including the studs and nuts and I failed to put any anti-seize on the threads before assembly. As a result, one nut seized while installing it and I was forced to cut it off and replace it with another. Then another seized while I was trying to disassemble it in order to put anti-seize on it (oh, the irony!), and I had to cut that nut off as well. In the end I had to run a die over the threads of both of the studs from which I had cut the nuts and then put non-stainless nuts on. It was a fiasco of my own making, but it ended up alright. Just beware! Use anti-seize when using stainless nuts on stainless bolts or studs!
head stay, also from Baxter. Aluminum this time.
Here's the Burkhardt magneto cap. It would not fit at first on my Hunt magneto, but there was plenty of material available to make it fit after some time with a sanding drum equipped Dremel. I went with the Burkhardt for a couple reasons, 1.) because I like the threaded connectors that hold the spark plug wires in and 2.) because I haven't seen anybody else do it! Preliminary testing shows a nice hot spark, as there should be.
I've got a question for you guys. What goes here, on this big threaded plug? It looks like a huge banjo fitting should go here, but I don't seem to have one:
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Or similar (IIRC!):
Though more likely it should have had one as seen here (sorry, my memory ain't what it was!) :
Motorcycle parts and spares for Norton motorbikes - Genuine Andover Norton Spare Parts - Andover Norton Motorcycles Parts - Original Andover Norton Parts
Motorcycle parts and spares for Andover Norton motorbikes: Andover Norton manufactures and supplies all Genuine Factory Spare Parts for Norton motorcycles built before 2002.
andover-norton.co.uk
Though more likely it should have had one as seen here (sorry, my memory ain't what it was!) :
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That longer oil tank fitting could be used for attaching a hose to a banjo fitting to make oil changes easier. Using the bolt shown left of image on the oil tank that is supposed to be a drain plug is in a tight spot and difficult to get a funnel under. I can't see why an additional gravity feed line would be used on a P11 at all. Ponderous. Whatever the case, consider getting the one shown by Longtimegone, or getting the big banjo and figuring out what to use it for.
If your fitting does not have a screen up top, I would not use it without adding an oil filter to the feed line.
If your fitting does not have a screen up top, I would not use it without adding an oil filter to the feed line.
Junglebiker
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I think that one would actually work better for me, as the in there now is resting against the frame and even tightened down onto a banjo fitting it would still be hitting the frame. Thanks!
Junglebiker
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If I could find the appropriate barb fitting, I'd screw it into where the drain plug currently is, then put a stout rubber hose on it with a plug in the bottom like some Harleys have. Makes it super easy and clean to change the oil.
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